Method of electric welding



Patented Aug. 30, 1927.

UNITED STATI-:s

THOMAS E. IUBRAY, JB., l' BROOKLYN, NEW YORK.

IETHOD 0F ELECTRIC WELDING.

Anuman mea mgm 1a, ma. serial No. 582,866.

My invention aims to provide an improved method of joining two parts of sheet `0I? other metal by welding them in a way having certain advantages over the usual methods.

The. accompanying l'drawings illustrate embodiments of the invention.

Figs. l and 2 are cross-sections illustrating successive steps in making a joint.

`Referring first to Fig. 1, two parts. 1 and 2 of sheet metal are to be united edge to edge. I first place between 'them a joint member having a web 3 filling the space between the edges of the .parts 1 and 2 and having Vflanges 4 overlapping the edges of the parts 1 and 2. The parts thus assembled are held between two electrodes 5 and 6, the former having a recess 5? to accommodate the projecting end of the .web 3 of the joint members. The electrodes are pressed together to hold the parts against each other :ind a current is passed sufficient to soften the metal and to effect a weld between the overlapping portions ofthe joint member and the parts 1 and 2 to be united. The weld will first take lace between the sheets and the flanges 4, since the contact surface between these is in the most direct path for the current and sincethe pressure is exerted mostly at these points. The current may be applied in such volume and for such a eriod, however, as to .effect avweld also between the web 3 and the'edges of the parts j l :ind 2.

Another electrode 7, Fig. 2, is then substituted for the electrode 5 and the parts again pressed together and the current passed between the electrodes 7 and 6. The electrode 7 has a hollow end shaped to upset and spread the end ofthe joint member so as to form flanges 8 which overlap the edges of the parts 1 and 2 and, by a continuation ol the pressure, the overlapping flanges'S are welded to the sheet metal parts 1 and 2.

If desired the projecting parts of the joint member may be softened and pressed together sufliciently to bring one or both of -them substantially flush with the surface of the parts 1 and 2.

The )roduct thus obtained presents a more A attractive appearance than the ordinary butt welded joint with its irregular burrs projecting from the surface, and avoids the expense heretofore involved in the removal of such burrs.

The method 1s also more convenient in some respects than the usual butt-welding operation for joining two sheets because of the comparative difficulty of 'clamping'the sheets to the electrodes so that they may be pressed togetherby means of the electrodes.

Though I have described with great parvticularity of detail certain embodiments of my invention, yet it is not to be understood therefrom that the invention is restricted to the particular embodiments disclosed. Various modifications in the detailsand in the apparatus employed may be made by those skilled in the art without departing from the rinvention as defined in the following claims.

What I claim is- 1. The method of electrically welding two parts together which consists in providing a joint member with a web wider than the thickness of said parts and with a pair of flanges, both at one edge of the web, placing eachl of the two parts with one of its faces against one of said flanges and an edge against said web, pressing said parts against the flanges and passing a welding current across the contacting faces of said parts with said flanges so as toform welded joints be- .tween such faces and, after said welded joints are formed, upsetting and spreading the projecting portion of said web to overlap it on the edges of said parts.

2. The method of electrically welding two sheets 1 and 2 together which consists inl providing a joint member with a web 3 of greater width than .the thickness of said sheets and with a pair of flanges 4, both at one edge of said web, placing the two sheets together each with one of its faces against one of said `flanges and with anedge against said web, pressing said sheets against said flanges by means of electrodes and passing a welding current between the electrodes.

THOMAS E. MURRAY, JR. 

